Cool, I like how this parser can model the &quot;Look, an Eagle&quot; scenario. For reference:<br><a href="http://www.youtube.com/watch?v=pjh3e198pUQ">http://www.youtube.com/watch?v=pjh3e198pUQ</a><br><br>The parser can &quot;change focus&quot; (that is, change traversal strategy) in response to a successful parse. In the &quot;Look, an Eagle&quot; scenario, the bear is able to interpret and respond to its input serially and interactively, but when the bear&#39;s input stream is replaced by a new one, the man is able to capture the prize.<br>